[Python] Why does not scapy recognize my custom layer?

In scapy I've added a layer with "bind_layers". But it seems that I did something wrong and a packet is not recognized correctly.

I try to add a layer to scipy and don't understand where am I wrong.

from scapy.data import ETHER_TYPES
from scapy.fields import XBitField, BitFieldLenField, ShortField, XShortEnumField
from scapy.layers.l2 import Ether, Dot1Q, LLC
from scapy.packet import Packet, bind_layers


def remove_layer(pkt, pos):
print('remove_layer N = ' + str(pos))
payload = pkt[pos].payload
pkt[pos - 1].remove_payload()
return pkt / payload


def remove_hsr(pkt):
print('remove_hsr')
print('layers:')
for layer in pkt:
print(layer.name)
if HSR in pkt:
print('HSR is here')
j = 0
for layer in pkt:
if layer is HSR:
print('HSR layer index: ' + str(j))
return remove_layer(pkt, j)
j += 1
print('remove_hsr : HSR not found')
return pkt


class HSR(Packet):
name = "HSR"
fields_desc = [
XBitField("path_id", 0, 4),
BitFieldLenField("lsdu_size", 0, 12),
ShortField("sequence_number", 0),
XShortEnumField("type", 0x9000, ETHER_TYPES),
]


bind_layers(Ether, HSR, type=0x892f)
bind_layers(Dot1Q, HSR, type=0x892f)


pkt_nohsr = '0060089fb1f300400540ef24000e810000200800450000a43b3b40004006b7548397208183972015048a17704e14e0754d3d609980187c70b13900000101080a0004f0c90199a3f3420007001d00c0000800c00000005e00d9025e00d9020000d9025e00420007001d00c0000900c00001005d00d8025d00d8020100d8025d00420007001d00c0000700c00001000100d80201000100010001005d00420007001d00c0000a00c00000000000d90200000000000000005e00568034cb'
pkt_nohsr = bytearray.fromhex(pkt_nohsr)
pkt_nohsr = Ether(pkt_nohsr)
print(pkt_nohsr)
pkt = '0060089fb1f300400540ef24892f10b60000000e810000200800450000a43b3b40004006b7548397208183972015048a17704e14e0754d3d609980187c70b13900000101080a0004f0c90199a3f3420007001d00c0000800c00000005e00d9025e00d9020000d9025e00420007001d00c0000900c00001005d00d8025d00d8020100d8025d00420007001d00c0000700c00001000100d80201000100010001005d00420007001d00c0000a00c00000000000d90200000000000000005e00568034cb'
pkt = bytearray.fromhex(pkt)
pkt = Ether(pkt)
print(pkt)
print(remove_hsr(pkt))


My header here is '892f10b60000' where '892f' is an indicator of my type. I connected my layer with Ether and Dot1Q because those are possible lower layers. This code produces the output:

802.3 00:40:05:40:ef:24 > 00:60:08:9f:b1:f3 / LLC / Raw / Padding
00:40:05:40:ef:24 > 00:60:08:9f:b1:f3 (0x892f) / HSR / Raw
remove_hsr
layers:
Ethernet
HSR is here
remove_hsr : HSR not found
00:40:05:40:ef:24 > 00:60:08:9f:b1:f3 (0x892f) / HSR / Raw


print(pkt) does not recognize inner layers with HSR added. HSR in pkt is true, but for layer in pkt has only 1 iteration with layer == Ether. What did i do wrong?

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